The present invention relates generally to electrical and electronic circuit structures, and more specifically to techniques for assembling electrical and electronic circuitry.
Printed circuit boards are known and have been widely used in the assembly of electrical and electronic circuitry. Such circuit boards typically provide mechanical support for a number of electrical and electronic components while also defining various electrically conductive circuit paths thereon. Additionally, some modern printed circuit board technologies include the lamination of metallic back plates for further mechanical support, thermal management of the various electrical components attached thereto and/or to provide for electrical net connections.
An example of one known modern printed circuit board arrangement 5 is illustrated in FIG. 1 and includes a circuit board 10 having a metallic film 14, such as copper (Cu) for example, affixed to at least one side thereof to define a printed circuit board 12. In FIG. 1, the metallic film 14 is shown as being affixed to a back side of circuit board 10, although additional films 14 may be affixed to the top side of circuit board 10 and/or within circuit board 10 and interconnected in a predefined manner as is known in the art. In any case, the printed circuit board arrangement 5 is conventionally assembled by attaching electrical components 16, 18 and 20 to printed circuit board 12 and electrically interconnecting such components via known means prior to attaching the assembled circuit board 12 and 16-20 to a metallic back plate 22 via a thermally conductive yet electrically insulating adhesive 24. The metallic back plate 22 is typically a copper or aluminum plate that provides support and rigidity to circuit board assembly 12 and 16-20 while also acting as a heat sink for dissipating heat generated by one or more of the electrical components 16, 18 and 20.
An example of another known modern printed circuit board arrangement 30 is illustrated in FIG. 2 and includes a printed circuit board 12 having a number of electrical components 16, 18 and 20 attached thereto via known means to thereby provide a circuit board assembly 12 and 16-20. A support assembly 32 is formed by affixing a number of segmented metallic bus structures to a rigid metallic plate 22 via a thermally conductive yet electrically insulating adhesive 24. Three such bus structures 34a, 34b and 34c (collectively defining a composite bus structure 34) are shown in FIG. 2, and are typically formed of copper (Cu) or Aluminum (Al) as is plate 22. The circuit board assembly 12 and 16-20 is then affixed to the support assembly 32 via an electrically conductive adhesive 36. The circuit board arrangement 30 is thought to be superior to circuit board arrangement 5 of FIG. 1 because the bus structure 34 provides for more direct heat sinking capability of individual electrical components as well as an added means for electrically interconnecting circuit paths defined by circuit board assembly 12 and 16-20.
While the foregoing printed circuit board arrangements are widely used in the automotive and other industries, they have certain drawbacks associated therewith. For example, while both arrangements provide at least some heat sinking capability, neither arrangement provides for efficient thermal dissipation with respect to individual ones of the electrical components 16, 18 and 20. As another example, arrangement 30 does not provide for electrical and mechanical connection of any of the circuit components 16, 18 and 20 to any of the various bus structures 34a-34c, nor does it provide for electrical and/or mechanical connection to any of the bus structures 34a-34c external to circuit arrangement 30. Finally, arrangement 30 requires pre-assembly of the electrical components 16, 18 and 20 to circuit board 12 prior to attachment of the bus structure 34 thereto. Such an arrangement thus allows electrical interconnection only between the various bus structures 34a-34c and an electrically conductive film, such as film 14, patterned on the backside of circuit board 12.
What is therefore needed is an improved printed circuit board arrangement utilizing a segmented bus structure that provides for greater overall thermal dissipation capability, increased heat sinking efficiency with respect to individual electrical components mounted to the circuit board, allows for high current interconnections to the bus structure and electrical and/or mechanical connection to the bus structure of one or more of the electrical circuit components as well as circuitry external to the circuit board.
The foregoing shortcomings of the prior art are addressed by the present invention. In accordance with one aspect of the present invention, a method of forming an electrical circuit comprises the steps of attaching a conductive bus structure defining a number of bus segments to at least a first surface of a circuit board, at least one of the bus segments extending through the circuit board from the first surface to at least an opposite second surface, and mounting a first electrical component to either of an opposite surface of the circuit board and the at least one of the bus segments extending through the circuit board from at least the first surface to at least the second surface.
In accordance with another aspect of the present invention, a method of forming an electrical circuit comprises the steps of attaching a conductive bus structure defining a number of bus segments to at least a first surface of a circuit board, a first surface of at least one of the bus segments defining a terminal end of a passageway extending into a second opposite surface of the circuit board, mounting an electrical component to the at least a first surface of one of the bus segments defining the terminal end of the passageway, and electrically connecting the electrical component to at least one circuit node defined on the second opposite surface of the circuit board.
In accordance with yet another aspect of the present invention, a method of forming an electrical circuit comprises the steps of attaching a conductive bus structure defining a number of bus segments to at least a first surface of a circuit board, at least one of the bus segments extending through the circuit board from the first surface to at least an opposite second surface, and electrically connecting the at least one of the bus segments extending through the circuit board from the first surface to at least an opposite second surface to a circuit node defined on the opposite second surface of the circuit board.
In accordance with still another aspect of the present invention, an electrical circuit comprises a circuit board defining a first surface and a second opposite surface, a bus structure defining a number of bus segments, the bus structure mounted to at least the first surface of the circuit board with at least one of the number of bus segments extending through the circuit board from the first surface to the second opposite surface, and an electrical circuit defined on the second opposite surface of the circuit board, the at least one of the number of bus segments extending through the circuit board from the first surface to the second opposite surface connected to a circuit node forming part of the electrical circuit.
In accordance with a further aspect of the present invention, an electrical circuit comprises a circuit board defining a first surface and a second opposite surface, a bus structure defining a number of bus segments, the bus structure defining a first surface mounted to at least the first surface of the circuit board with at least a portion of the first surface of at least one of the number of bus segments defining a terminal end of a passageway extending into the second opposite surface of the circuit board, and an electrical component mounted to the at least a portion of the first surface of at least one of the number of bus segments defining a terminal end of a passageway extending into the second opposite surface of the circuit board, the electrical component electrically connected to a circuit node forming part of an electrical circuit defined on the second opposite surface of the circuit board.
One object of the present invention is to provide a combined circuit board and segmented conductive bus assembly that overcomes drawbacks associated with prior art structures. These and other objects of the present invention will become more apparent from the following description of the preferred embodiment.